I am at my wit's end. I have a 2016 300s with the Pentastar v6 engine.
1. Got a misfire on 5 and found the spark plug tube had oil in it.
I changed all the spark plugs to "NGK 93175 Iridium IX" and changed the spark plug tube gasket.
2 Tested it, still misfire.
3. saw that there is some oil in the tube still. Changed the seal out again and I switched the coils around.
4. STILL MISFIRE!!!!!

So now I am worried that it is something much bigger. Any ideas???

I am at a serious loss here. I just made my last payment on this car this month. And earlier this year, I had to spend $7K to fix my Ram's camshaft after a misfire in the same cylinder (coincidental, but seriously!). At this point I don't think I will be purchasing a Chrystler or Ram ever again.

 

Ok, to give everyone a laugh, I figured out the issue shortly after posting this. The problem was that in the whole process, I was working on Cylinder 6 and not 5!!! This is about as stupid as it gets, but cylinder 6 had oil in the spark plug tube so in my head I was thinking I was working on the right issue. The real issue was simply a coil gone bad in 5. Easy quick fix. On a good note, my wife 300 got new spark plugs and gaskets.

For those ADHD individuals like my self. If facing the engine with the belts forward, the left side is odd numbers, and the right side (under the header) is the even cynlders.

 

Good on you OTHERJOHN.